Automatic carriage return



Nov. 5, 1957 H. c. YAEGER 'AUTOMATIC CARRIAGE RETURN 2 Sheets-Sheet 1 Filed NOV. 12, 1953 INVENTOR. HARRY C MEGA R ATTORNEY H- C- YAEGER AUTOMATIC CARRIAGE RETURN Nov. 5, 1957 2 Sheets-Sheet 2 lNVENTOR HARRY c. YAEGER ATTORNEY n m A; 2 v 4 u i198 I,

n m m W A 2,812,049 Patented Nov. 5, 1957 United States Patent Ofiice AUTOMATIC CARRIAGE RETURN Harry C. Yaeger, West Hartford, Coum, assignor to Underwood Corporation, New York, N. Y., a corporati n. of Delaware Application November 12, 1953', Serial No, 391,640

2 Claimst (Cl- El -66) This invention relates to typewriting and similar machines having on a frame an advanceahlc and. returnable carriage, and more particularly relates to control mechanisms for such machines whereby a normally i'dle powerreturn mechanism for the carriage is automatically called into operation when the carriage advances to av predetermined position.

The machine of the invention embodies a tabulating mechanism for advancing the carriage rapidly to desired columnar positions. In connection with such tabulating mechanism the machine embodies further means that is effective to suppress or check rebounding; of; the carriage V,

resultant from the sudden arrest thereof at the end of each tabulating run. Due to the provision of said rebound checking means, a carriage controlling escapement assumes at the end of each tabulating run, immediately and reliably, the appropriate position control over the carriage, and, moreover, the machine is immediately ready for resumption of typing.

As will be evident from the detailed description of the machine which follows, said rebound checking means prevents also movement of; the carriage in return direction for a, short interval of time after the carriage, in a tahulati'ng run, reaches a certain position defined by a car riagerreturnsinstituting control element. Therefore, it will be appreciated. that if a power-return run of the ear ri'ag'e were to get under way while the rebound checking means still blocks the carriage. against; return movement, than the power return; mechanism would become stalled and inoperative.

To the. end. of providing an efficient. machine,..incorpo'rating a power carriage return mechanism which is rendered active automatically under carriage control, and. incorporati also a carriage tahulating mechanism. long. with de irable.- and efiicient rebound uppr ssing: means, i i an bj ct of the invention to provide efiicien means to enable automatically the powerreturn; mechanism, under carriage control by a. carriage return instituting element but. with a Sufficient: delay so that, the power return mechanism will become active only after the stated; rebound checking means has done its work and is, or has moved from operative position.

Other objects of the invention will become. evident in the light of the detailed description of a preferred embodi ment of the invention, which follows.

Now having reference to the drawings,

Fig r 1. is a r gh -hand sectional side ele a ion of a typewriting machine embodying acarriage and a carriage tahulating mechanism,

Figure 2 is a bottom elevation of a typewriter escap ment unit along with a tabulation rebound checking mech anism in an idle relation to. an escapemcnt wheel, the rear of the machine being towards the top, of the, view,

Figure, 3. is a bottom elevation similar to Figure, 2 v but th t bul ting rebo n checking mechanism i hown moved to an active position,

Figure v4 is a bottom elevation as Figures 2 and 3 are, showing the rebound suppressing mechanism about to become inactive,

Figure 5' is a perspective illustration of a carriage re- 2 turn control mechanism in normal position, the direction of vision being forwardly and downwardly from the rear of the machine, towardthe. right,

Figure 6. is a left-hand side elevation of certain parts of the carriage return control mechanism; seen in Figure 5, in their normal positions,

Figure 7 is a view similar to Figure 6 but certain of the parts are shown operated,

Finally, Figure 8 is a fractional rear elevation, showing a carriage return clutch in open position, along with a related controlling mechanism.

Referring nowvmore particularly to Figure 1 of the drawings, a typewriter framework 10 comprises opposite side walls 11 and a trackway 12. A carriage 13, by means ofa carriage rail 14, is guided upon said trackway 12 for opposite travel in advance and return directions. Said carriage 13- includes ends 15 carrying a platenroll 16 which is adapted to support work sheets for reception of typing impressions, all in a usual manner. Above and to the rear of the rail 14 the carriage 13 supports a rack bar- 24 having thereon at letter space intervals, usual keysettable tabulating stops 17'.

A frame-supported spring motor 18 has an operative connection. with the carriage 13, in a usual manner, for urging itirnpositively to advance leftwardly, that is, in lotter'feeddireetion. However, in a conventional manner, movement of the carriage in the letter feed direction is controlled by an escapement generally designated by the numeral 19, in cooperation with an escapement wheel 20-. The latter rotates synchronously with the movement of the carriage, a rack 23 on the. carriage rotating a gear 22 and the latter being connectedv with the escapement wheel 20 through a shaft 21. 4

Normally the carriage is held at restagainst the urge of the spring motor 18 in that one of the teeth on the 31. On the top side the rocker 30 carries a usual; step ping dog 32 which normally is clear above the teeth of the escapement Wheel 20, and held advanced in respect to the, holding dog 27 by means of a spring 33. The spring 33 also servesto bias the holding dog 27 into the orbit of thewheelteeth.

Incidental, toeach typing operation the escapemeu-t rocker 30. is. vibrated in a usual manner, first to swing the, dog 27 downwardly clear of the. active wheel tooth hereby to free he carriage to take a. letter feed t p under power of the spring motor 18. This swings the. stepping dogiiz into. intercepting position of. the next, wheel tooth, nd aft r he scapcmcnt rocker 30 has vibrated oppositey, h d g. og 7 will be in control of the. next tooth 28. During carriage returns the escapement Wheel 20 rotates in a direction opposite, to the arrow indicated inv Figure 2 and the. teeth of the escapemeut, wheel 20 crowd the escapement dog 27 idly outwardly,

The. illustrated machine is shown to embody the power.- actuated tabulating mechanism of the patent to Helmond,

No. 2,303,878, dated December 1, 1942, Said tabul'ating mechanism comprises, a counterstop reed 37 which is projectable upwardly fromthe position seen inv Figure, 1,, into the range of any set tabulator stop 17,. At operation, of a. tabulator key 38,, a transversely extending lever 39 swings downwardly to depress a lever 40 having seen in Figure I. The actuator receives a forward power 1 gagement with the toothed shaft 52. There ensues then an operation of a link 56 which rocks a structure 57 includinga shaft 59 about an axis defined by the. latter. This structure 57, by means of alink158" and a lever 60 imparts an upward movement tothe reed 37.- The upper end ofthe reed 37, reacheszthr'ough a-perforation provid ed in a top plate 63 of atabulator housing 64 and spring means 67 biases the reed downwardly and rightwardly. Said perforation is wide enough to allow some lateral movement of said reed 37 and so that at projection ofrthe reed a latch edge 65 thereon will catch rightwardly over a plate 66. Whenever the reed 37 is proected, the lever 60 operates a bell crank 68 carried plvotally at 70. During the first part of the projecting movement of the reed 37 a downreaching arm 71 of the. bell crank 68 moves first idly from the position seen in Figure 2. After the upper end of the reed 37 has moved above the lower edge of an active tabulator stop 17, said arm 71 will pick up and swing the holding dog 27 clear of the escapement wheel tooth which has to this moment been active. The carriage resultingly takes a tabulating run in letter feed direction until a tabulator stop 17 engages and displaces the projected reed 37 leftwardly to the limit in the perforation. This places the latch edge 65 free of the plate 66 so that the spring 61 associated with the reed will retract the latter to normal position. During such retraction of the reed, the downreaching arm 71 of the lever 68 swings rearwardly and renders the holding dog 27 free for movement to effective position under the power of the spring 33, see Figure 2. The movement of the arm 71 in regard to controlling the dog 27 is such that the latter will move to holding position before the tabulator reed 37 moves fully below the tabulator stop 17.

The sudden violent arrest of the carriage at the encounter of the tabulator stop 17 with the reed 37, especially after long tabulating runs, results in violent rebounding action of the carriage, and the machine includes means which at the end of each tabulating run is eifective to check rebounding of the carriage, thereby to assure the eventual settling of the carriage in the proper letter feed position.

The particular rebound checking means shown in that of the patent to Yeager, No. 2,647,611, issued August 4, 1953, and includes a reverse rotation checking pawl 76 for the escapement wheel 20, pivotally carried at 77 on the underside of the escapement bracket 25. The pawl 76 occupies. normally a position fully clear of the orbit of the teeth of the escapement wheel, see Figure 2. At each institution of a tabulating run the downreaching arm 71 of the bell crank 68, through the intermediary of a connection comprising an interponent rod 78, imparts a forward swinging motion to a lever 80 reaching in Figures 2 and 3 leftwardly from a pivot point 81 on the bracket 25. Toward the end of the forward swinging motion of the lever 80 a pin 82 engages a rear face on a lever 84 to swing the latter to the position seen in Figure 3. The lever 84 is pivotally carried by a stud 85 on the bracket 25 and is yieldingly connected with the reverse-rotation check pawl 76 by a spring 87. Therefore, when the lever 84 is in the operated position seen in Figure 3, the spring 87 urges the pawl 76 into reverserotation checking relation with the escapement wheel 20. During the movement of the levers 80 and 84 to their operated positions seen in Figure 3, a latch element 88 pivotally carried at 90 on the lever 80, facilitated by a spring 91, glides over an ear 92 on the lever 84 to arrive finally in the position seen in Figure 3. During tabulating movement of the carriage, and while the tabulator reed 37 remains projected, the lever 80 remains operated and therefore the check pawl 76 is posed for aci tion. During the tabulation the escapement wheel 20 the escapement wheel teeth ratcheting past the check pawl 76 idly. As the tabulator stop 17 meets the counterstop 37, one of the escapement wheel teeth will have passed slightly beyond the check pawl 76 and the latter will spring-move into rebound checking position behind such tooth. When the tabulator stop 17 encounters the counterstop reed 37, it will displace it leftwardly free of the plate 66 for restoring action under the power of the spring 61. Before the reed 37 restores, the active tabulator stop will have displaced the reed 37 leftwardly to the full limit and the carriage 13 rebounds. The rebound check pawl 76 meanwhile stands ready in position to stop reverse rotation of the escapement wheel 20, as shown in Figure 3, said check pawl 76 being backed up by a mo tion limiting pin 96. During an initial portion of the restoring movement of the counterstop reed 37, before the same moves below the tabulator stop 17, the escapement wheel dog 27 moves to the escapement wheel controlling position seen in Figure 2. Meanwhile, the back check pawl 76 is held active by the latch 88 in cooperation with the car 92.

After the parts assume the position seen in Figure 4 v the reed concludes its retracting movement and the lever arm 71 assumes the normal position of Figure 2. During the very last increment of retracting movement of the reed 37 the pawl 88 rides off the edge of the car 92, wherefore the reverse-rotation check pawl 76 stays active sufficiently late beyond the instant of rebounding action of the carriage. The spring 91 therefore returns the lever 84 to the normal position seen in Figure 2, an arm 86 forcing the pawl 76 to idle position. carriage 11, under the power of the spring motor 18, settles in the exact desired letter feed position.

Additionally to the rod 78, the connection between the arm 71 and the lever comprises extending therebetween a spring 97 having the said rod 78 accommodated in the turns thereof. The spring 97 is very strong and always confines rod 78 snugly between the arm 71 and an adjustable screw 100 on the lever 80. The effect is that the rod 78, the spring 97 and the screw 100 constitute together an adjustable connection between the arm 71 and the lever 80, it being understood that the screw 100 is so adjusted that the latch 88 will mave clear of the eat 92 at the last possible moment of the restoring movement of the arm 71, thereby to keep the check pawl 76 sufliciently long capacitated to perform its intended function.

The machine of the invention further embodies a power return mechanism for the carriage. Such mechanism may be generally of the design disclosed in the patent to Helmond, No. 2,262,676, dated November 11,

1941, but is not limited thereto.

Referring now to the rear elevation of Figure 8 there is shown a carriage return clutch element 102 which,

while the machine is in use, is constantly driven by the return drawband passes upwardly over a guide sheave 111 and thence to the left carriage end whereat it is connected to a line spacing mechanism, not shown. The pulley 108, under the tension of a weak clock spring, not shown, keeps the drawband 110 lightly wound thereupon. The parts just described are located at the rear 1 of the machine near the right side wall 11.

The clutch member 104 has a spline connection with the pulley 108, as indicated at 109, and normally, as stated hereinbefore, is separated from the clutch member 102 Meanwhile the Axially in line with i and thus normally is not motor driven. A clutch conl i g f k 1 c ri on a shaft 11.3, is. associated with the clutch member 4 in the groove 105 thereof to shift it between an open and a closed clutch position. Said fork 112 is operable to the closed clutch position by lever 114 that is pivoted at 115', and. has a, link con nection 116 with an arm 117 fast upon the shaft 113. A spring 118 constantly tends tov have a clutch elosing in.- fluence on the fork 112. Normally, however, see Figure 5,, the described mechanism is held against the power of the spring 118 in open-clutch position by a latch 120 that is pivotally carried at 121 upon the outside of the right side wall 11 of the machine, The said latch 120 is biased to the effective position by a spring 122 and is releasable in a conventional manner under control of a carriage return key, not shown. Said latch 120 is also releasable under carriage control, automatically, by mechanism to be described presently, The carriage 13 upon a rack 123 carries a carriage return instituting element or stop 124, as well as a carriage return terminating stop 1244:, see Figure 5, said stops being adjustable along said rack, respectively to different return instituting and return terminating positions. As the carriage lettersteps or tabulates to the return instituting position defined by the stop 124, the latter engages, and displaces a short distance. in letter feed direction a counterstop element 125 on the machine frame. Such counterstop element may be in the form of an upright arm arranged at the rear of the machine pivotally upstanding and rockable about a stud 126 between limits afforded by a perforation 127 provided in the top plate 63. of the tabulator housing. Normally, when viewed from the front of the machine, the said counterstop arm 125 bears under the tension of the spring 128 against the right limit afforded by said perforation 127. When said return instituting element 124 displaces the counterstop arm 1 leftwardly (rightwardly in Figure 5), then a pin 130 on the latteroperates a bell crank 131 which also is pivotally rockable. on the stud 1 26. Upon a rightwardly extending portion of said bell crank 131 there is carried pivotally at 133 an adjunct arm 134. An ear 13.5 On the arm 134 normally abuts the underside of the adjacent portion of the bell crank 131. This is under the urge of a spring 136 extending between the car 135 and another car on the bell crank 131. Articulated to said arm 134 in an upreaching relation is a releaser 137 for the latch 120, having an offset nose 138 underlying normally idly an car 140 on the latch 12th, the nose being communicative through a hole in the wall 11. At the upper end said releaser embodies a fork 141 straddling a guide pin 143 projecting inwardly from the right side wall 11 of the machine.

In the movement of the carriage to the return instituting position, the carriage-carried element or stop 12 4 displaces the counterstop element 125 leftwardly as seen from the front of the machine. It will be evident later herein that if such movement is effected independently of the tabulating mechanism, such as by letter-feed motion of the carriage, arm 134 will become operated immediately with the bell crank 131 and will move the releaser 137 promptly upward, the nose 138 swinging the latch 120 clear of the clutch closing lever 114, it being understood that the spring 136 is stronger than the latch restoring spring 122. At release of said latch 120, the lever 114 snaps upwardly to clutch closing position under the tension of the spring 118. The fork 112, in such movement engages the clutch element 104 with the companion clutch element 102. Consequently there ensues a power return run of the carriage. The lever 114, under the tension of the spring 118 stays in closed clutch position while the carriage returns, and, moreover, a stud 143 on a member 144 that extends leftwardly from an upreaching arm of the lever 114 will then have moved leftwardly to keep the counterstop arm or element 125 against the left edge of the perforation 127.

Ul im t ly in he p wer return run of the carria the return terminating stop 124g; engages and moves forcibly the counterstop arm or element 125 rightwardly as seen from h front. The st d 143 is hus also moved ri wardly and this results in the restorationof the lever 114. to the control of the latch thereby rendering the carriage return clutch open and terminating the return r n of t e car iage.

A return run of the carriage may also be instituted as a result of a tabulating movement of the carriageto the return instituting position defined by the carriage carried element 1Z4. At the end of a tabulating movement to suGll Position, neither the tabulator reed, nor the before-described rebound checking element 76 must obstruct the return run of; the oarriage. Accordingly, pro vision is made so that as the carriage in its tabulating movement reaches return instituting position and the counterstop element is moved leftwardly, an arm 145 carried fast on such, counterstop element 125 moves also the tabulator reed 37 leftwardly. This frees the reed l g 5 Q n. he shelf 66 and the reed 37 restores downwardly under the urge of the spring 61. The carriage is then free, to return insofar as. the tabulating reed 37 is concerned, but its return must. yet be delayed to give the carriage rebound check Pawl 76 time to move clear O e 6 961 6 1 Wheel before. the. carriage return drive becomes active. According to the invention, provision is made so that in connection with a carriage return institlltiOIl ultan from. a. tabulation, the control over the power return'clutch 102, 1104 is such that the return run of the carriage will start only after the check pawl 76 has moved to idle position following the tabulati'ng movement. Specifically, there is provided near the right side Wall of the machine. fast: on the shaft 59 of the tabulating control mechanism, an upreaching arm-146. When the tabulating mechanism is in normal position, as in Figure 1, then said arm 146 is in the position seen in Figure 6 In such position of the. arm 146 a spring 151 holds a slide element 147 so that an car 148 thereof lies rearwardly of the longer prong 149 of the fork 14.1. The

said prong 149 is thus normally free for upward, carriageareturn instituting movement and this condition prevails also whenever the carriage is moved to the return instituting position without, use of the tabulating mechanism. Therefore, Whenever the carriage is advanced independently of the tabulating mechanism to the position in which the element 124 operates the counterstop 125, then the operation of the return instituting latch 120 is instantaneous. On the other hand, whenever the tabulator key 38 is operated the power actuator 51 rotates the shaft 59- so that the arm 146 moves from the position seen in- Figure 6 to the position seen, in Figure 7. Initially in such movement the spring 151 draws the slide 147 forwardly until it is intercepted by a pin 153 on the frame. This places the car 148 into a blocking position over the latch releaser prong 149. The arm 146' has a pin-and-slot connection 150 with the slide 147 and the spring 151 is provided, intermediate the slide 147 and the arm 146. to. allow the latter to complete its movement after the slide 147 is intercepted by the pin 153', as seen in Figure 7. The ear 148 reaches the position seen in, Figure 7 immediately in the stated movement of the arm 146 and during the remainder of the movement the spring 151 yields.

The arm 146 remains operated in each tabulating operation until the tabulator reed 37, upon being freed for downward movement, either by the tabulator stop 17 or the leftward operation of the arm 145, arrives in fully restored position. Thus, only in the very last part movement of the arm 146 from the Figure 7 to the Figure 6 position does the car 148 free the releaser prong 149 for upward movement. If the carriage moves toward return instituting position consequential to a tabulating operation, then the carriage supported return instituting ement .2.4 will encounter and operate the counterstop 125, operating the bell crank 131; Inasmuch as in tabulations the releaser 137 stands blocked by the car 143, the movement of the bell crank 131 will not be transmitted to the arm 134 but will cause the flexing of the spring 136, placing the arm 134 under a strong upward bias. The releaser remains blocked by the ear 148 until the tabulating mechanism, including the reed 37, approaches fully restored position, at which time the arm 146 forces the slide 147 rearwardly, to the Figure 6 position, and thereby forces the ear 148 otf the prong 149. This frees the releaser 137 for upward movement under the bias of the spring 136 which has remained flexed by the bell crank 131. The rebound checking pawl 76 which during the tabulation has been potentially held active by the pawl 88 restores to normal position at about the same instant. A little before, the arm 71 of the tabulating mechanism places the escapement dog 27 into cooperative relation with the escapement wheel.

It will thus be perceived that although the return instituting element 124 is allowed to operate the element 125, the releaser 137 functions to release the latch '120 only when the tabulating mechanism assumes completely restored position and the rebound checking mechanism is incapacitated. Upon release of the latch 120 the clutch fork 112 closes the return clutch under the power of the spring 118. The carriage then commences to be power-returned after the drawband 110 has operated the line spacer.

The provision of the spring 136 intermediate the bell crank 131 and the arm 134 allows the carriage to tabulate fully to the return instituting position. Therefore, the arm 145 on the return instituting counterstop ele ment 125 at the end of a tabulation to line-end position will always displace the tabulator reed 37 to cause its restoration, as well as the restoration of the entire tabulating mechanism including the blocking element 147. If the yield provided by the spring 136 were not provided, then the counterstop element 125 would be incapable of operation during a tabulation and in turn the arm 145 on the return instituting element 125 would be incapable of causing the restoration of the tabulating mechanism. The blocking element 147 would therefore remain in effective position and no automatic return could ensue.

The operation of the return instituting element 125 occurs ina movement of the carriage equivalent to a letter feed step thereof and results in an operation of an arm 155 indicated in Figure 5 to operate a type key locking mechanism, not shown.

All carriage return runs called into operation independently, of a tabulating operation, including such called into operation by a return key, not shown, occur without delay. Carriage return operations ensuing on the other hand due to tabulating movement of the carriage to return instituting position are instituted with a delay sufiicient to give the described rebound checking pawl 76 time to withdraw and free the carriage for power return movement.

Having explained the nature and the objects of the invention, and having specifically described a machine embodying the invention in its preferred form, what is claimed is:

l. The combination with a typewriting machine having a carriage movable on a frame in advance and in re turn directions, of a power return drive adapted to be closed and opened, means movable from a normal to an operated position and reversely, respectively to close and open said power return drive, spring means biasing said movable means to close said power return drive, a latch mechanism normally holding said movable means in normal position. a carriage-carried carriage return instituting element, an element carried on the frame for operation by said carriage return instituting element at advance movement of the carriage to a certain position, tabulating mechanism for the carriage comprising a tabulator stop, a counterstop ltcy-projectable into tabulation-terminating range with said tabulator stop, and means responsive to the encounter of said tabulator stop with said counterstop to retract said counterstop automatically, a normally idle device responsive to the retraction of said counterstop to check rebounding of the carriage momentarily and incidentally thereto obstructing momentarily movement of the carriage in return direction, means responsive to the operation of said frame-carried element by said carriage-carried carriage return instituting element, to retract said tabulator counterstop if it has been projected, means conditionable for resilient releasing action on said latch mechanism by the operation of said frame-carried element, and a member moved into a release-bl0cking relation with said conditionable means by the projection of the tabulator counterstop, and moved out of such blocking relation by the retraction of such counterstop, said conditionable means and said member having shoulders movable transversely to each other which are correlated so that the shoulder on said member moves into blocking relation with the other shoulder initially as said counterstop is being projected and conversely moves clear of such other shoulder only when said counterstop reaches substantially fully retracted position, whereby if said frame-carried element is operated as a result of a tabulation, the release of said latch mechanism ensues only as said tabulator counterstop be comes fully retracted, giving time for said rebound checking device to function and withdraw before the carriage begins its power return.

2. The combination with a typewriting machine having a carriage movable on a frame in advance and in return directions, of a power return drive adapted to be closed and opened, means movable from a normal to an operated position and reversely, respectively to close and open said power return drive, spring means biasing said movable means to close said power return drive, a latch mechanism normally holding said movable means in normal position, a carriage-carried carriage return instituting element, an element carried on the frame for operation by said carriage return instituting element at advance movement of the carriage to a certain position, tabulating mechanism for the carriage comprising a tabulator stop, a counterstop key-projectable into tabulation-terminating range with said tabulator stop, and means responsive to the encounter of said tabulator stop with said counterstop to retract said counterstop automatically, a normally idle device responsive to the retraction of said counterstop to check rebounding of the carriage momentarily and incidentally thereto obstructing momentarily movement of the carriage in return direction, means responsive to the operation of said frame-carried element by said carriage-carried carriage return instituting element, to retract said tabulator counterstop if it has been projected, means conditionable for resilient releasing action on said latch mechanism by the operation of said framecarried element, and a slide moved into release-blocking relation with a part of said conditionable means by the projection of the tabulator counterstop and moved out of such blocking relation by the retraction of such counterstop, said slide having a shoulder movable transversely to the operating path of said part, initially as said counterstop is being projected, and said shoulder being moved clear of said part only when said counterstop reaches substantially fully retracted position, whereby if said frame-carried element is operated as a result of a tabulation, the release of said latch mechanism ensues only as said tabulator counterstop becomes fully retracted, giving time for said rebound checking device to function and withdraw before the carriage begins its power-return.

References Cited in the file of this patent UNITED STATES PATENTS Yaeger Jan. 22, 1946 Sagner Aug. 4, 1953 Yaeger Aug. 4, 1953 i 

